1. Field of the Invention
The present invention is directed to a coil for a magnetic resonance system, having an antenna with which a magnetic resonance excitation signal can be emitted and/or a magnetic resonance signal can be received.
2. Description of the Prior Art
Coils of the above type are well-known. They are employed both rigidly mounted at the system and as loosely arranged local coils.
Given such a coil, it is important to identify its presence in the magnetic resonance system. When a coil element of a coil is situated within an excitation field of the magnetic resonance system, it can lead to great stresses on the surrounding tissue due to a locally elevated RF excitation field if it is not appropriately detuned by a control signal. Identification of which coils are present in the system and which are not present therein must be made in order to be able to correctly operate the coils that are present.
A known identification technique is to acquire the presence of the coils via terminal plugs. In the prior art, the terminal plugs are individually coded at the coil side in order to be able to determine which coils are situated in the magnetic resonance system.
This known procedure is disadvantageous because, first, only connected coils can be identified and, second, there is only a limited number of coding possibilities by means of the terminal plugs. For example, 256 coil types can be distinguished given eight contact bridges that are optionally plugged or not plugged.
An object of the present invention is to provide a coil for a magnetic resonance system that can always be identified and that offers expanded coding possibilities.
This object is achieved in accordance with the invention in a coil for magnetic resonance system having a transponder from which data that are characteristic of the coil can be emitted given electromagnetic excitation.
When the transponder is fashioned as passive transponder, the transponder does not require its own energy source.
When the transponder transmits coil-characteristic data given excitation with a frequency within the bandwidth of the excitation coil, but beyond the magnetic resonance frequency range, it can be excitedxe2x80x94without modificationsxe2x80x94by the magnetic resonance system to transmit the coil-characteristic data.
The coil-characteristic data can include different types of information. A type code for the coil, a serial number for the coil, an internal system code for the coil, a system code and operation-specific data are examples.